Improvement in compensating watch-regulators



J. P. CLARK.

Improvement in Compensating Watch-Regulators.

N0. 114,644. l Patented May 9,1871.

WTNXSSXLS NVLNTOR.'

UNITED STATES PATENT OEEicEo JEDFDIAII I. CLARK, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN COMPENSATING WATCH-REGULATORS.

Specilication forming part of Letters Patent No. 114,644, dated May 9, 1571.

To all whom t may concern:

Beit known that I, JEDEDniI-I I). CLARK, of the city and county ot' Philadelphia., and State of Pennsylvania, have invented new and useful Improvements in Regulators for Vatches; and I do hereby declare the following to be a clear and exact description of the nature thereof, suiiicient to enable others skilled inthe art to which my invention appertains to fully understand and use the same, rct'ercncebeing had tothe accompanying drawings, making part of this specification, in which- Figure l is a top or plan View of the regulator of a watch with my invention applied thereto. Fig. 2 is a central longitudinal section thereof.

Similar letters of reference indicate corresponding parts in the two iigures.

It is well known that the balance-wheel of the most accurate wa-teh makes about eighteen thousand vibrations in one hour, and the greatest diiiiculty to be overcome in the regulation of a watch is to make those divisions ot' time equally exact. A poorly-constructed conipensatiiig-balance is almost certain to get out'of weight77 in expanding' and contracting, and the variation oi" a plain-balance watch, when subjected to the heat of the body, after it has been regulated to a uniform temperature of sixty to seventy degrees, is much more than most watch-makers appreciate.

My invention is designed to produce a reliable compensating-regulator5 and it consists in a curb or arm attached to and moving with the regulator, for the purpose of autoinaticallylengthening and shorteningtheworking part of the hair-spring relatively to the slightest change of temperature, virtually keeping the spring the same length in heat or cold.

Referring to the drawings, A represents the bridge ol" a watch, provided with the regulatorindex IE and scale O.

I) represents the compensating-curb. .lt

with the regulator. The inner side or piece of the curb is a metal that expands in heat and contracts in coldinuch more than steel. In the present case the inner side or piece ot' the curb is zinc. The expanding and contracting properties oi" zinc and steel in heat and cold are in a ratio ot' about four to one, (-it to l.) The curb is ot' curved forni, and one end is Afirmly attached to the index, as at l). The other end, c, is adjustably connected to a piece, d, which is pivoted to the portion G of the regulator, which carries the regulatingpins, which lengthen` and shorten the working part of the hair-spring, said portion Gv beingjointed to the other portion ot' the regulator. The curb can be readily lengtliened and shortened as required by sliding it in and out of the index, which is slotted i'or that purpose, and the end c can be attached nearer to or farther i'rom the center ot' the jointed portion G, and,` when once properly adjusted, it can be permanently l'astened or marked, so that in cases ol" subsequent removal it can be afterward replaced in the same spot. It will be seen that the curb does not interfere with the manipulation ot" ihe regulator proper, but moves with it as it sweeps over the scale.

rlhe operation is as l'ollows: Vhen the inner metal ofthe curb expands or contracts, it forces the pin end ot' the regulator in a circle corresponding with the hanf-spring, thus moving the pins to counteract the lengthening and shortening ot the spring-that is to say, in cases ot heat and expansion the hair-spring expands as well as the curb. rIhe hair-spring is thus lcngthened, and will cause the watch to run slower, but the expansion oi' the curb at once acts on the regulator in ,such amanner as to shorten the working part of the hairspring, and thus bring the speed ot' the watch to the proper regulation. In cases of contraction the hair-spring shortens and the contraction ol' the curb causes the regulator to lengthen the working part ofthe spring, whereby the speed is again equalized.

rIhe curb, ashereinbetore stated, can be applied to any kind of a watch, and will be found to be simple and practical for the purpose intended.

olziiln as new, and desire to Secure by Letters laterally, as described.

Pate11b,is- The above Specification of iny invention The Combination and arrangement of the Signed this 3d day of March, 1871.

Compound compensating curb or strip E F JEDEDIAH l. CLARK.

Wit-11 the regulating-arm or index B, and with- Having thusfdesoi'ibed my invention, what I l Swing-curb 'is caused to expand und oontmeb W'i messes:

the pivoted arm G, carrying the pins for adi JOHN A. XVlEinaRaiUci'ii,

l Poney Y. KNiciSS.

justing the 1mirspring, whereby the compen- 

